I’m only new to this myself, only assembled my Picade this week (got a few issues I need to post about in a few minutes). For the power switch, I found it easier to attach the wires with it detached from the Picade and then thread the wires through the hole . On the power switch you’ll find tiny + and - markings beside the two closer prongs (I needed to take a photo with a digital camera and zoom in to see them properly). Carefully attach the red wire to the + and black to the - (you might need to loosen the connectors a little before this, they’re very tight). Match the colours to the right spaces on the hat and hopefully that should clear up that issue. As for the sound, maybe make sure the power lines are in the right order and inserted fully into the hat?